Yamaha CS1X

True, the name harks back to the CS‑series synths of the '70s and '80s, but with their new CS1x, Yamaha definitely have their eyes set on the future. Critics Derek Johnson & Debbie Poyser analyse Yamaha's blue period...

After years of practically ignoring the grass‑roots revival of analogue synthesis and the demands of the market for the knob and arpeggiator‑laden instruments of yesteryear, the major synth manufacturers are finally cottoning on to the fact that there's money to be made in supplying that demand. They're rather late in jumping onto a bandwagon that's already pretty full with the likes of Novation, Quasimidi and other small companies who responded to the trend some time ago. But better late than never...

You may have already read the review of Roland's MC303 Groovebox that precedes this piece (see pages 84‑90). The MC303 can be seen as Roland's admission (at last) of the popularity of their TR909 and 808 drum machines, and their TB303 Bassline — and it looks like everyone's going back to their roots. Just as Roland have recycled the 303 from the TB303 and the MC from their MC202 microcomposer (also a hip second‑hand buy), Yamaha have revived the venerable CS prefix from their '70s‑'80s analogue synth line. The resulting stab at the dance market is the £599 CS1x, a sleek, good‑looking keyboard synth which marries the kind of modern 32‑note polyphonic, AWM2 GM/XG (General MIDI/Extended General MIDI) sound source we've come to expect from Yamaha with an additional 'Performance' synth section, a degree of real‑time knob control, an arpeggiator, and a PC/Mac computer interface.

Just The Knob

Aside from the fact that it's blue, the CS1x bears some resemblance to the Clavia Nord Lead (which, as you might remember from the May 1995 SOS review and front cover, is red). The 'knobular' section on the top left of the front panel is backed by a black‑screened area which reminds one of the screened blue panel on the same area of the Nord Lead. The CS1x even has a sheared‑off top left corner, similar to the Nord Lead's sheared‑off bottom left and top right corners. The insides of the two instruments, however, are not similar. The CS1x is not an analogue synth, nor even a virtual analogue synth, like the Nord Lead. Without being critical of the synth in any way, it's more of a repackaging of existing Yamaha S+S (Sample + Synthesis) technology, with a dance market presentation.

The eye‑catching case hosts a 5‑octave, velocity‑sensitive keyboard (but no aftertouch; the synth responds to aftertouch but the keyboard doesn't transmit it). The chunky pitch and mod wheels are on the left of the keyboard, and just above these is the collection of six knobs for real‑time sound tweaking (labelled Attack, Release, Cutoff, Resonance, Assign 1/Data, and Assign 2), plus a volume knob and two buttons labelled 'Scene'. The small custom LCD has an accompanying set of six black buttons, used broadly for selecting sounds or parts of sounds, plus a Shift button and a yellow 'Arpeggio' button. Pressing Shift and Arpeggio together freezes the current arpeggio. Next to the display on the right is the numeric keypad, used for patch selection and naming, and for entering parameter values when editing, if desired. Finally, there's an editing 'matrix': a row of 10 small 'rocker' buttons, above which is an area of text labels relating to editable parameters in the CS1x's Performance mode, including arpeggiator functions and effects. A rotary knob selects between horizontal rows of parameters, and you zero in on the parameter you want to edit by tapping the rocker switch that lines up with it vertically. Once you've selected a parameter, you change its value using the same switch. Values can also be changed with the Assign 1/Data knob, which doubles as a data entry knob while editing, or with the numeric keypad. Finally, there's a group of four buttons used for selecting between the CS1x's two operating modes (of which more shortly), storing edits, and selecting Utility mode: here, you access master tuning, set Global keyboard transposition (+/‑36 semitones), select a keyboard velocity curve, set MIDI channels, set local on or off, and initialise bulk dumping of Performances to an external storage device.

It's an odd thing, but arpeggiators have a vibe about them that other, more sophisticated, auto‑accompaniment tools lack.

The observant amongst you may spot a raised lip on the far right of the front panel. By total coincidence, this supports a Yamaha SU10 baby sampler, or a QY‑series baby sequencer, as if it was made for the job. Either of these units, but especially the SU10, would make a very nice partner to a CS1x, making one wish that Yamaha had given the synth a bit of sample RAM.

Rear connections comprise stereo output jacks, MIDI In, Out and Thru, a computer interface socket, and three foot‑controller sockets. There's also a quarter‑inch headphone socket, and a mini‑jack stereo input: this allows you to mix in another stereo source — a cassette deck or another synth, for example — and is ideal if you just want to jam by yourself.

The CS1x is extremely light; one reason for this could be that it uses the dreaded external power supply.

Multi Play Mode

The CS1x has two operating modes. Its Yamaha provenance shows in its GM/XG sound source, accessible in what Yamaha call Multi Play mode. Using this sound source alone, you might not suspect that the synth was aimed at the dance market at all — there's the usual comprehensive array of AWM2 voices (think MU50), 480 in all, plus 11 drum kits, and three effects processors, offering Reverb, Chorus, and 'Variation'. The latter is a mixed bag of delays, distortions, rotary speaker effects, and so on (see the 'Effect Types' box for more details). Multi Play mode puts the CS1x into gear as both a controller keyboard and a multitimbral sound source for use with a sequencer. The GM/XG voices, happily, respond to edits made with the real‑time control section on the front panel — which is similar in function to the real‑time edit controls on Yamaha's SY85 (although on that synth, the controls take the form of sliders). Like the SY85, four of the knobs offer control over envelope Attack and Release and filter Cutoff and Resonance of a sound. The remaining two knobs are assignable, but are reserved for use by 'Performance' mode — more on this in a moment. Aside from these 'tweaks', which can nevertheless be very effective, there isn't much more you can do with GM/XG voices from the front panel in Multi Play mode; you can, however, change volume and pan settings, and set effects send levels. More detailed editing would have to be done via MIDI SysEx, as with most GM synths. There are no user memories for edits in this mode, either.

Performance Mode

So far, so familiar. What's different about this instrument is its Performance section. This is basically a separate synth section with 128 dance‑orientated presets (Performances, in Yamaha‑speak) and 128 user memories for your own Performances — these are full of factory settings, but they can be written over. This section is not truly multitimbral, though its Performances can be composed of up to four elements (Layers, as Yamaha call them), which can be used in a stack, or split across the keyboard — but all on the same MIDI channel. The raw material for the Performance Layers is contained in 12 banks of up to 128 voices each, which adds up to a huge number of sounds you can use to create new Performances. You could almost think of these voices as waveforms, although they each behave much as a preset synth patch.

The emphasis of the Performance section is on what you'd expect from the name — real‑time Performance. In accordance with its 'real' synth feel, Performance synth sounds can be properly edited, parameter‑access style, from the CS1x's front panel, as well as tweaked with the six real‑time control knobs; the two assignable knobs which don't work in Multi Play mode can be assigned in Performance mode to any of 28 parameters per knob, which range from traditional synthesis parameters to arpeggiator tempo and mod wheel cutoff. You can also assign a volume pedal‑type foot controller to a variety of MIDI Controllers.

Performance mode is really where the editing matrix comes into its own. It's not possible to start from a completely initialised patch, but you can comprehensively edit the CS1x's Performances from the matrix. There are 20 parameters common to a Performance as a whole, plus 40 parameters that can be set individually for each of the four Layers (see box 'Performance Synthesizer Parameters' for a list). For a synth in this price range, that's considerable editability and compares favourably in terms of sonic control and accessibility with more expensive instruments.

The best programming strategy is to start with a Performance that's close to the result you're after, or you could set up a neutral 'initial' Performance — four Layers of simple sine waves, for example — and save it in the User bank. There is no convenient way to mute Layers during editing (as with an SY85, say), so fine‑tuning individual Layers can be a little awkward. However, if you want to use the same settings for a parameter on all Layers in a Performance, simply press 'Shift' while editing the selected parameter.

Performance mode is also where the arpeggiator resides. This offers 30 arpeggio types and only works with Performances (including drum and percussion‑based Performances), not with the GM/XG voices in Multi Play mode. Although 30 arpeggio styles doesn't seem like a huge amount, this is actually a comprehensive selection (see box 'Arpeggio Styles'), and a range of 10 timing sub‑divisions is available, which can change the feel of a pattern completely. An arpeggio's tempo can be set between 40 and 240bpm, or clocked from an external MIDI device. For a little more flexibility, it's possible to split the keyboard at middle C so that the lower half is arpeggiated while the upper half isn't, allowing you to play chords or melodies unimpeded. It's an odd thing, but arpeggiators have a vibe about them that other, more sophisticated, auto‑accompaniment tools lack. And if you've been wondering, no, you can't define your own arpeggio styles, which is a shame.

How The Modes Work Together

Fortunately, the CS1x's Multi Play and Performance modes can work together to some extent, although you wouldn't really know it from the manual. In Performance mode, you can have 12 GM/XG parts from the CS1x (including drums on MIDI channel 10) playing via a sequencer, as a backing track, while you wibble, solo, and arpeggiate with the Performance section. Live, this would enable you to have a full‑sounding backing while maintaining some performing spontaneity. In the studio, the same situation would pertain, but you could be recording your real‑time wibblings into the sequencer too. Note that the arpeggiator does not transmit its arpeggios as individual notes over MIDI. It's essentially a playback device, and if you want arpeggios as part of a sequence, you have to record the chords you want arpeggiated (you'll be hearing them being arpeggiated, as usual, while you play) and then have the arpeggiator work on the recorded chords as they play back.

There's more overlap between the GM/XG voices and Performance mode when it comes to sounds. Performances, as mentioned, can be made up from sounds in the 12 banks of basic voices, but you're also allowed to make up Performances using GM/XG voices as the Layers. Once you've got the required GM/XG voice into a Performance, you can use all the synth's editing facilities on it: if you really must edit and arpeggiate that GM Bassoon, you could make up a Performance using just that voice. So there are some links between the two modes of the CS1x, which is all to the good as far as sonic potential is concerned.

Real‑Time Control

The real‑time editing knobs allow on‑the‑fly tweaking of the essentials of a sound — and that includes drum sounds. This facility is immediate, hands‑on, and fun — and pretty close, in terms of feel, to using the control knobs of an analogue synth. It's also well‑implemented, in that there is hardly anything in the way of digital 'stepping' when the knobs are moved: it only occurs slightly when you wiggle the Cutoff knob with the Resonance set full on. The knob tweaks are sent out over MIDI too, so you can record them into a sequencer. Some sounds respond better than others to real‑time editing, because the knobs aren't transmitting absolute values but are providing a positive or negative offset to a parameter's current value — if a Performance is already pretty resonant, for example, you'll only be able to back off the resonance, rather than add more. As mentioned earlier, the four main labelled knobs, EG Attack and Release, and Filter Cutoff and Resonance, work on both Performances and GM/XG voices; you can save a Performance edited in this way by simply pressing the Store button, but you won't be able to easily store tweaked GM/XG voices — there are no memories on board for these. This is a shame, but you could put a tweaked GM/XG voice into a Performance and then store it in a Performance memory.

A neat addition to the CS1x's real‑time control section is its 'Scenes'. These are two memories which store 'snapshots' of the knob settings for a Performance. You can store two differently‑tweaked versions of a Performance and swap between them for predictable timbre changes, which is very useful and could be a good way to get out of a mess if you've wiggled too far... Each Scene button has an accompaning LED which lights when it's pressed, and when a Scene is selected, the editing knobs become inactive. If you press both Scene buttons at the same time, the mod wheel (or a connected volume pedal‑type foot controller) crossfades between the two versions. Both the Scene and Scene crossfade functions are an attempt to recreate some of the real‑time fun of analogue synthesis, and they work very well.

Effects

The CS1x's three effects processors (whose sound quality is fine, by the way) provide a fairly comprehensive selection of treatments. Reverbs and choruses are the job of the first two, and the third, Variation, provides choruses and reverbs plus more unusual treatments. Variation effects are always 'insertion' effects, which let you specify which voice will be treated by the effect. The classic example used to illustrate this concept is the ability to put a distortion effect on an electric guitar patch without having the backing turn into Nine Inch Nails! The distortion in this example would be an insertion effect.

While the Variation effects are indisputably insertion effects in Multi Play mode, in Performance mode you can specify that all four Layers of a Performance are effected by the same insertion effect. If you have GM/XG voices playing as backing while in Performance mode, you can't use the insertion effect on the GM/XG voices.

The real‑time editing knobs allow on‑the‑fly tweaking of the essentials of a sound.

Having said that the Variation effects are always insertion effects, we should point out that there is a way of making them behave as ordinary 'system' effects: you have to send the synth a MIDI Control Change message from an external device (a sequencer, for example). Likewise, MIDI Control Changes need to be used if you want to change effect types in Multi Play mode, which is a bit of a pain — the three effects default to Hall 1, Chorus 1 and Delay L,C,R.

Effect editability isn't really available on the CS1x: the Reverb and Chorus effects can't be edited from the front panel, although given the right piece of MIDI software, all parameters are accessible over MIDI — for example, reverb time, diffusion and LPF cutoff on reverbs. The Variation effects are fully editable from the front panel, but only in Performance mode.

In normal use, the Reverb and Chorus effects are accessed by a send control. Each Layer of a Performance has its own send level, which allows you to set the right amount of effect for each Layer. The same goes for Multi Play mode, where each part has its own send level. As noted above, Variation effects are always 'insertion' effects unless you tell them, via MIDI, to become system effects. As Insertion effects, they can either be on or off; when they're told to behave as a system effect, the on/off switch becomes a send level control.

Sounds

As already mentioned, the CS1x's GM/XG voices come from Yamaha's MU50 sound module (see review in SOS September 1995). It's a serviceable collection, with no real disappointments, and quite a few highlights, including the lovely harp and some brass and woodwind that's a cut above the rest.

What you'll be most interested in is the Performance presets. Many of these have been programmed from brand new waveforms with the dance market in mind, and there's a good selection of analogue‑sounding leads, basses and pads. The presets eventually give way to generic impressionistic, washy pads, but there's plenty to be going on with until you start programming for yourself. Favourites include User patch 11, 'Squelchy', a boingy, detuned, modulated, LFO‑heavy sound that works especially well arpeggiated; User patch 17, 'Ethno', an instant Gamelan reminiscent of the soundtrack to the cult Japanese animation Akira; and User patch 31, 'Glassy', a sharp, chugging 3‑'oscillator' stack that makes an instant track when used with the arpeggiator. Though S+S can't deliver quite the same power and presence as analogue, for a digital synth the CS1x's filter is pretty good, and most people won't find anything to complain about in its sounds: many of the presets show very imaginative programming.

Conclusion

Though the CS1x uses technology already employed in other Yamaha instruments, the whole is definitely greater than the sum of the parts. The arpeggiator and real‑time editing controls are great fun, and the Performance section enables you to emulate a monotimbral analogue synth if you want to, while still being able to have a GM/XG backing. In fact, one gets the feeling that the GM/XG mode was almost an afterthought, as though Yamaha weren't sure that a purely Performance synth would sell in the '90s. The few negative points include the fact that the GM/XG side is relatively inaccessible without the intercession of MIDI SysEx, as is detailed editing of the effects. You can't define your own arpeggio patterns, and you can't select a waveform from scratch for editing — you always have to work from an existing voice. Finally, the arpeggiator doesn't transmit over MIDI, which would have been nice.

Having said all this, the CS1x is really superb value for money — look at what you get: a keyboard whose design makes it look as though it should cost rather more than £599, featuring a full GM/XG synth section, plus the Performance mode, arpeggiator, real‑time editing, 32‑note polyphony, three effects processors, one of which provides an insertion effect, and a PC/Mac computer interface. It's relatively simple to use, and the sounds will do you proud. In all, it's a highly desirable little instrument.